Thermostatic control of carburetors



A, TAUB THERMOSTATIC CONTROL OF CARBURETOR Filed May 29, 1.926

abtozmgz lull Patented Dec. 11, 1928.

"IT-ED STATES PAL-TENT; oFncE.

ALEX TAUB, OF DETROIT, MIGHIGAN, ASSIGNORTO GENERAL MOTORS CORPORATION,

015 DETROIT, MICHIGAN, A. CORRORATION OF DELAWARE.

THERMOSTATIG GONTROL 0F UARBURETDRS.

Application filed May 29, 1923. Serial No. 112,381.

This invention relates to internal combustion engines and is concerned with means for automatically changing the character of the fuel mixture in accordance with the needs of the engine.

'lhe invention is intended for use on a steam cooled or constant temperature engine. warming up period a richer mixture is needed. than at normal running temperature. The carburetor is adjusted for the normal engine temperatures. Before. the engine reaches that .normal tem erature the fuel supply is insuificient un ess provision is made for additional supply.

It is an object of the invention to provide means automatically operable to supply a relatively rich mixture during the period in which the engine is warmin up and to leanthe mixture when the engine has reached its normal running temperature.

For the attainment of this object I make use of a thermostat subjected to the heat condition of the chamber containing the cooling medium and provide; a connection between the thermostat and thecarburetor fuel supply means whereby the proportion of fuel in the mixture is automatically.

changed.

The invention is herein described in detail and is illustrated in the accompanying drawing: I

Figure 1 shows an internal combustion engine of the constant temperature type in side elevation, the fuel control of this invention being incorporated therein.

, Figure 2 is a side elevation of a carburetor having parts broken away and in section.

Referring by reference characters to the drawing, numeral 1 represents the internal combustion engine as a whole. The oil pan is shown at, 2 and 3 re resents the head mounted on the cylinder lock. Numeral 4 is theexhaust manifold and 5 represents the intke manifold. The carburetor is shown at i Within the head 3 and contained within the chamber receiving the chamber from the cooling medium which surrounds the cylinders is a thermostat 9. This thermostat is of well known bi-metallic type. Extending to the outside of the head 3 is a stem 11 having an arm 13. Under the action of the It is well known that during the thermostat stem 11 rotates and swings the arm 13. I

Referring more particularily to Figure 2 the carburetor is shown as having a float chamber '15, a throttle valve chamber 17 and an air inlet 19. There is also a valve 21 which may be opened by the suction of the motor against the tension of the spring 23. At the lower side of the carburetor there is Shown plug 25 throu h which passes the needle valve 27. The e1 reaches the needle valve by passage 29 from the float chambers 15. At t e left of-the needle valve 27 there is shown a second plug 31 which has'a circumferential groove 33 and a radial passage 35, the latter communicating with an axial passage 37. Extending through this plug is a second needle valve 39 cooperating with a seat 41 in a tube 43 secured within-an opening in the plu 31. The stem of the needle valve is enlarged and fits snugly where it passes out through the plug 31, packing 45 and a cap 47 being su plied to make the joint tight. The end of t e needle valve stem is threaded as at 4.9 where it is engaged by a collar 51. The collar is engaged by the forked ends of a lever 53 ivoted at 55 to an arm 57 extended down from the bottom of the carburetor. A link 59 is connected between the arm 13 of the thermostat and the'lever 53.

By the mechanism described it will be seen that the movement of the thermostat controls the secondary valve 39. When the engine is cold and an additional supply of fuel is needed for the mixture the condition of the thermostat is-such that it, through the arm 13, link 59 and lever 53, opens the secondary fuel valve. When, however, the engine warms up and reaches that temperature for which the carburetor is adjusted the thermostat agailr acts through parts 13, 59 and 53 to close the secondary needle valve. It will be understood that the thermostat is located within that part of the cooling chamber where it is sub ected to the hot vapors arising from the cooling medium WlllOll surrounds the engine cylinders.

I claim: 1. In a constant temperature engine, a chamber for cooling medium therefor, a thermostat therein, a carburetor having primary and secondary means to supply uel mixture to said engine, mechanism connecting said thermostat and the secondary supplying means for said carburetor where- ''by the thermostat determines the character of the mixture.

2.111 a constant temperature engine, a chamber for cooling medium therefor, a thermostat therein, a carburetor having means to supply fuel mixture to said engine,

said means including a primary fuel valve 10 and a secondary fuel valve, operating means between said thermostat and said secondary fuel valve for controlling thesupply of fuel through'said valve in accordance with the temperature of the medium to which said 15 thermostat is subjected. v i

In testimony whereof I afiix my signature.

ALEX TAUB 

